Apparatus for refining sublimable material



Dec. 18, 1945. F. J. HANSGIRG 2,391,156

APPARATUS FOR REFINING SUBLIMABLE MATERIAL Filed Feb. 4, 1942 3 Sheets-Sheet 1 J 14W 4m 10% Dec. 18, 1945. F. J. HANSGIRG APPARATUS FOR REFINING SUBLIMABLE MATERIAL 3 She ets-Sheet 2 Filed Feb. 4, 1942 Jrwenzfor air/w, o 6' Dec. 18, 1945. F. J. HANSGIRG 2,391,156

APPARATUS FOR REFINING SUBLIMABLE MATERIAL Filed Feb. 4, 1942 s Sheets-Sheet 5 Patented Dec. 18,. 1945 APPARATUS FOR, anrmmc SUBLIMABLE MATERIAL Fritz J. Hansglrg, Los Altos,- Calif., assignor, b3

mesne assignments, to The Anglo California National Bank of San Francisco, San Francisco,

Calif., trustee a national banking association, as

Application February 4,1942, -ser1a1 No, 429,484

4 Claims. (01. 266-19) My invention relates to an apparatus for refining vaporizable, especially sublimable material such as metals, and has in the first instance in view a device which is adapted for refining, by sublimation, crude, alloyed or impure magnesium, particularly magnesium dust as is obtained as an intermediate product in the course ,of the carbothermic reduction of magnesium oxide-containing material according to my patents Nos. 1,884,993 and 1,943,601. This dust includes not only impurities coming from the ore started with,

but also considerable amounts of magnesium oxide and carbon.

In my copending applications s. N. 380,589 filed February 26, S. N. 387,643, filed April 9, and S. N. 411.784, filed September 22, all in 1941, of which this application is a continuation in part, I have disclosed a process and an apparatus especially suited for freeing this dusty intermediate product from said impurities by a sublimation operation capable of being commercially carried out so as to produce ma n sium of outstanding purity at a reasonable cost. The herein disclosed apparatus is an improvement on that described and claimed in my aforesaid prior applications, and while embodying the same general principles of operation and construction contains in addition thereto features which permit closer control of the process.

A further object'of my present invention is, to

vapor evolved, a liner removably positioned in the condenser member spaced-from the walls thereof, and means adapted to establish proper communication between the'interior of the charge and the condenser. According to a preferred mode of execution of my invention this means is centrally situated within the charge so as to reduce, by I displacement, the radial extent thereof. Moreover, this means are preferably constructed such as to permit controlling, the speed of the vapor rising in the condenser.

The removable liner provided in the condenser member to cause the sublimed magnesium to condense thereon and thus to facilitate the removal of the sublimate, is known to the art by itself.

It is, however, an important feature of my invention that this liner be positioned so as to provide an annular interspace between the outer face of the liner andthe inner face of the condenser wall coacting with said outer face ofthe liner through a seal for preventing the vapor from rising in the interspace. This arrangement aims at avoiding sudden cooling down of the hot metal vapor and results in obtaining the sublimate in a coarse or even massive crystalline condition which is a considerable advantage, since the melting loss is markedly decreased thereby.

There may moreover be a charge container with a discharge opening in its bottom placed removber adapted to be kept cool for condensing the ably in the retort member in which case the means adapted to establish proper communication between the-interiorof the charge and the condenser, is constructed such that it operates at the same time as aremovable locking mechanism for the discharge opening of the charge container.

An apertured partition may be placed between the retort and condenser member.

As disclosed'in my prior applications, I prefer to superimposethe condenser member upon a substantiallyvertical retort member. According to the preferred mode of execution, the apparatus consists of a'icylinder-shaped retort having a protracted upper'p'art adapted to serve as a con-' denser.

"Now in order to acquaint those skilled in the art-"with the manner of constructing and operating an embodiment of my invention, I shall describe, in conjunction with the accompanying drawings forming a part of this specification, a specific embodiment of the invention and the mode of use'of the same;

Referring to the drawings:

Figure 1 is a vertical longitudinal section through the apparatus embodying my invention;

Figure 2 is a top plan view of a liner disposed in the upper part of the apparatus; f

Figure 3 is a top plan view of a partition positioned between the upper retort and condenser member;

Figure 4 is a section'taken on the line 4-4 o jF ure 1;

Figure 5 is a bottom plan view of a vapor flow the lower part of the apparatus;

Figure 6 is a fragmentary section taken on an enlarged scale, showing details of the removable cover of the apparatus and of parts associated therewith;

Figure 7 is a fragmentary sectional view on an 7 enlarged scale, illustrating details of the vapor flow regulator:

Figure 8 is a fragmentary section taken on the line H ofFigure2;

Figure 9 i a view of details in connection 'with Figure 2;

Figure 10 is a fragmentary section showing aflange 4 and with a yielding seal ring 6. Hinged bolts I mounted on hinges I in ears- I swingup through slots formed in the flanges 4 and I for releasably clamping the cover 2 to the cylinder Iwhich cover is supported in suspension on a flange II and provided with reinforcing brackets l and a bracing ring III to render the flange II rigid. The brackets 9 are perforated as indicated at I2 to form cars by which the cylinder I can be removed from its mounting II. This mounting comprises the under zone I4 heated by the electric resistance conductors I6 which are mounted on suitable insulating refractories I1, and an upper zone I 5 containing a cooling coil It.

The mounting I3 includes an outer shell I! and an inner shell 2I l, both of metal with insulation indicated at 22 between them. The outer shell I! is closed at the bottom 28 and has an inwardly tapered or conical wall 22 atits upper end which terminates in a double walled neck portion, 24 surmounted .by the flange 2|. This flange is slotted to cooperate with the slotted flange II, hinged bolts 28, and1a sealing ring. 2' to produce an air-tight Joint. A vacuum pump connection is indicated at. 30 communicating .with

winding having the three phase terminals 33 leading to the outside with a groundconnection such as 34, common to the two of them. One or more pyrometers as indicated at 25 may-beprovided at suitable points in the mounting. The two sets of heater conductors are independently controllable for applying and distributing the desired amount of heat. The cooling coil I5 is preferably made .of steel tubing having an inlet connection at l! and an outletconnection at 31. All of these connections are made airtight with the outer shell.

The cover 3 of cylinder I hasa main convex wall 3. arched upwardly and provided with guiding flns 29 around its periphery. An outer thin wall of sheet metal 40 is welded to the flange 5 and spaced from the main wall 3|, thereby providing a suitable air space for the thermal insulation of the cover member 38 (Figure 6). At its center the cover member 3 is provided with a short neck 42 surmounted by a clamping flange 43. A vacuum connection 44, controlled by a valve 45, is releasably connected -to the tubular connection 42.

denser part of cylinder I comprises a series of releasable flanged sections, for instance four in number. These flanged sections '2, 82 (Figures 2 and 9) have longitudinally extending mating flanges 82. II which are provided with-registering holes, with wedge bolts 04 projected through said holes, and with wedges I! projected through slots in the shanks of the bolts '4. The section .2 are provided at their upper ends with circular flange sections I! which may be Joined to a common cover member 81 (Figure 2). The flanges 8| are provided with bolt holes whereby the marm of the cover member '1 may be bolted to the flanged sections it by the usual bolt and nut attachment, as indicated at II. The removable liner II is placed in the condenser part in such ,position as to provide an annular interspace 60' between the outer face of the liner and the inner face of the condenser wall, sealing means for preventing the rising of vapor from the retort part of the cylinder I into said annular interspace being provided.

The retort part of the cylinder I which is within the heating zone maybe provided with a thin walled steel cylinder 4! slidable in the retort cylinder I, which bucket serves for receiving the charge. The lower end of this bucket 46 has an inclined flange 41 (shown in detail in Figure 7) which rests upon the bottom wall 2 of cylinder I (Figure l) At its upper end, the bucket 46 coacts with the wall of cylinder I through a sand.

seal. Ribs or flanges 4!, which project radially inwardly (Figures 1 and 4) are welded to the side wall of the bucket to perform the dual function of reinforcing and serving as heat conductors to the charge which is disposed in the bucket in contact with them. Convenient means for lifting the bucket out of the retort are provided. The lower end of the bucket 4. has an opening II (Figures 1 and 7) for discharging the spent charge. This opening is normally closed by the vapor flow controlling means 52 which is formed of a series of annular louver members 53 (shown in section in Figure '1) having the shape of hollow truncated cones with the parts of smaller diameter being disposed under the parts of larger diameter of the next upper ring. These rings may be rigidly connected with longitudinally running flns or strips 5!, which are preferably disposed, as appears from Figure 4, alternating with the ribs 49. A pair of rings or eyes 59 are provided for lifting and lowering the vapor flow controlling means as unitary structure. -As appears irom Figure '7, bottom ring 54 rests against the flange 41 and thereby closes off the opening II. This lowermost ring constituting the valve ring, is braced intemally and reinforced by radially extending strips or braces 56 which are welded together to a junctionring 51 at the center. At its upper end the vapor flow controlling means I! is provided with a conical cap or cover "which is perforated to form a screen.

Between the retortmember and the condenser member there is provided a partition III with a central opening I3 through which the vapor released from the charge passes into the interior of the liner 60 (Figures 1 and 3). This opening is surrounded by a funnel-shaped wall I4 for guiding the charge into the charge container. The funnel I4 is reinforced by gussets or bracket-like webs ll welded in place. Ears or rings I6 provide convenient means for lifting the partition III out of, the way when it is desired to withdraw the charge container 40.

The removable liner OI positioned in the con- In the modified form of construction correspending to Figure 11, in which there is shown a retort I, the apertured partition 18 is releasably connected to the lower end of the liner 88, so

. that the partition can be drawn out of the retort flange 12 forms a seal between plate 18 and the retort wall I through the medium of the sand lutlng 50.

As shown in Figures 1 and 2, the cover of the removable liner 60 comprises a circular disc 61 with a central aperture and having bolt holes around its outer margin for clamping it to the flanges 86 at the upper ends of the liner sections 82. This disc is reinforced by a series of radially extending gussets or braces 11 which join the disc to a central funnel-shaped member 18, the lower end of which is continued as a cylindrical tube 19. Disc 61 is perforated as illustrated in Figures 2 and 8, and the perforations are covered with a screen 80. The tubular duct forming the extension of the funnel 18 terminates above the funnel 14 in the partition 10. It is provided with a valve consisting of a disc 83 resting upon lugs 82 welded to the inside of the lower end of the tube 19. A valve stem 84 extends up to a point within the funnel 18 where a convenient handle 85 (Figure 2) permits the withdrawal of the valve and stem from the charging tube 19. The valve stem is held in central position by a spider near its upper end.

A restriction 88 is disposed between the upper and lower section of mounting l3, to prevent radiation of heat from the hot zone to the cold zone without cutting off the communication with the vacuum conduit. This is shown in detail in Figure 10. A pair of rings 81 and 88 are welded to the side walls of the cylinder l and an annular cylinder member 89 providing a depending flange 90 is welded to the outer margins of the annular rings 81 and 88 to provide a dead air chamber which may be pierced by tubing stays 92. The depending annular flange 90 telescopes loosely with a similar upwardly projecting annular flange 93 supported on the shoulders of the inner metal lining 20 of the retort mounting.

The entire assembly is mounted vertically upon a suitable foundation.

The operation of the device described is as follows:

The cover 3 is removed and liner 60, partition 18, bucket 46, and vapor flow regulator 52 are brought in place. Then the valve 83 is withdrawn from the charging tube 19 and the charge, which may consist of pellets or tablets of com"- pacted magnesium powder, is fed in through the funnel 18 and the charging tube 19. This material drops down through the opening 13 and is spread by the cone 58 in the open annular space between the fins 49 on the inside of the bucket 46 and the fins or strips 55 on the outside of the vapor flow regulator. Thereupon the valve 83 is replaced, the cover member 3 securely fastened in position, -and vacuum applied,

through connections 44 and 30, to produce a residual pressure below 2' mm. as well in the interior of the cylinder l, as in the interspace surrounding it. Heat is now applied to maintain the charge at a temperature below the melting point of magnesium. The vapor disengaged passes through the lateral openings of member 52 into the central channel formed by the interior'of the superimposed rings thereof, escapes through the perforations in the cone 58, and rises then through the aperture 'I3.of partition 78 in the condenser 82, where it condenses as a thick annular deposit of massive crystalline character adhering to the inner face of the liner 60.

There follow the steps of completely cooling down, opening cylinder I, and lifting out the liner 68 for recovering the sublimate. If not connected to the liner 60, the partition 18 is then removed separately. The charge container 48 with the vapor flow regulator 52 and residue contained therein, can now be drawn out of the retort and passed to a, suitable point, where, by raising the flow regulator with its valve member 54, the spent charge is discharged by gravity through opening 5i. Finally the vapor flowregulator 52 is dropped down into position closing the opening 5|, and the bucket 45, partition 10 and liner 80 are rearranged in their proper places as shown in the assembly of Figure 1 for repetition of the cycle.

In case no bucket 46 be used the removable liner is supported, for example, by angles, fastened to the container wall to hold the liner in proper position within the condenser. In this case the spent charge is discharged by turning over the container to tilt out the residue from the retort.

I claim:

1. An apparatus for extracting metal in the vapor state from material bearing such metal, comprising a longitudinally extended retort member closed at the bottom and adapted to be heated for evolving vapor from material charged therein, and superimposed thereupon an elongated condenser member provided with a removable cover and adapted to be kept cool for causing the vapor evolved to condense thereon as a solid deposit, in combination with a removable liner positioned in the condenser member so as to provide an annular interspace between the outer face of the liner and the inner face of the condenser member wall, and a charge container with a discharge opening in the bottom, liftably placed in the retort member; means for establishing proper communication between the interior of the charge and the condenser member, adapted to control the speed of the vapor rising in the condenser member, and constituting a liftable blocking mechanism for the discharge opening of the charge container and being substantially centrally positioned in the retort member, so as to reduce by displacement the radial extent of the charge under treatment.

2. In a retort, a substantially vertical retort cylinder having a closed bottom, a removable charge container disposed in the lower end of the cylinder, said charge container comprising a bucket having an opening in the lower end thereof, a central tubular member having lateral openings, the lower end of said tubular member constituting a removable closure for said opening.

3. In a retort, a substantially vertical retort cylinder having a closed bottom, a removable charge container disposed in the lower end of the cylinder, said charge container comprising a bucket having an opening in the lower end thereof, and a valve member for closing said opening, said valve member having an operating member disposed at the upper end of said charge container, whereby the charge container may be liited out of the cylinder and the valve member raised to dump the bucket. 1

4. In a retort, a substantially vertical retort cylinder having a closed bottom, a removable charge container disposed in the lower end of the cylinder, said charge container comprising a bucket having an opening in the lower. end thereof, and a lift valve member closing the said opening in the bucket.

FRITZ J. HANSGIRG. 

